Electronic devices are increasingly being incorporated within vehicular tires. These electronic devices may include sensors and other components suitable for obtaining information regarding various physical parameters of the tire, such as tire pressure, tire temperature, number of tire revolutions, vehicle speed, and the like. Such information can be useful in tire monitoring and/or warning systems. Indeed, tire pressure monitoring systems (TPMSs) are commonly utilized for monitoring the tire pressure of a motorized vehicle. Typically, the tire performance information is transmitted to a vehicle-side transceiver of the motorized vehicle. Thus, electronic devices located at the wheel can include wireless transmission circuitry. Furthermore, a microprocessor may be employed in order to collect and process the signals coming from the sensors before transmission.
Such integrated tire electronics modules must be supplied with electric power for operating their sensor elements, for processing the sensor signals, and for transmitting the signals to a vehicle-side transceiver. Thus, such electronics modules are typically powered by a non-rechargeable battery located within the tire electronics. Unfortunately, the service life of the battery within an integrated tire electronics module is limited. For example, a battery for an integrated tire electronics module may last approximately six to ten years. However, a tire may have a lifetime of approximately five years, while a car may have a lifetime of ten years or more. Thus, the batteries or the entire module will likely need replacement during the lifetime of the vehicle. For example, the batteries or the entire module for each tire may need replacement shortly after replacing the tires, which is both inconvenient and expensive. Alternatively, as a preventative maintenance measure, operable integrated tire electronics modules with significant remaining battery life may be discarded and replaced at the same time as the tire, which is both wasteful and costly. Further, some drivers will ignore dashboard warning lights indicating that the batteries need replacement in order to avoid paying repair costs, thereby decreasing their safety.
Accordingly, eliminating the battery as the energy source for integrated tire electronics or at least extending the service life of the battery is desirable from a cost, reliability, safety, and environmental perspective.